The broad, long-term objectives of this research are to 1) contribute to the knowledge base of detrimental effects of treatment associated estrogen deprivation on cognitive function in post-menopausal women treated for breast cancer, and 2) provide a foundation for the design of interventions to assist women with breast cancer receiving adjuvant estrogen depriving therapies (AEDT). The two specific aims of this project are to determine whether 1) AEDT (e.g., tamoxifen or anastrozole) in post-menopausal women treated for breast cancer is associated with alteration in cognitive function over time as determined by objective and subjective measures of selective attention, working memory and verbal memory, and 2) the severity of decline in selective attention, working memory and verbal memory is related to the type of AEDT (tamoxifen or anastrozole) employed in this population. This project addresses NINR research priorities including the integration of biological and behavioral sciences and managing symptoms in chronic illness by delineating causative mechanisms that underlie symptoms. This project uses a repeated measures design in a convenience sample of 120 post-menopausal women: 80 receiving AEDT for breast cancer treatment and a comparison group of 40 healthy women. Objective measures of selective attention, working memory and verbal memory, subjective measures of selective attention and of possible covariates of depressed mood state, sleep quality, and fatigue will be obtained in women with breast cancer prior to beginning AEDT treatment and at 4 months after starting treatment. The same measures will be obtained at similar time periods in healthy women after a negative screening mammogram. Repeated measures analysis of variance will be used to test changes in cognitive function over time and differences in the two AEDT treatment groups vs. control group, and within the AEDT treatment group (tamoxifen vs. anastrozole). Analysis of covariance will be conducted as appropriate for relevant variables such as depressed mood state, symptom distress, sleep quality and fatigue. Relevance to Public Health: Breast cancer affects over 200,000 women yearly, mostly over the age of 50. Early stage breast cancer in most of this age group is successfully treated by decreasing levels of the body's natural estrogen. Because estrogen is present in the brain, this treatment may cause changes in thought processes that are essential to daily function at home, work and in society including the ability to focus one's attention, ignore distractions and keep in mind useful information. Information from this study will be used to develop ways to help women adjust to these cognitive changes. [unreadable] [unreadable] [unreadable]